The Osbornoceros (Osbornoceros osborni) was a prehistoric antilocaprid which is extremely similar to today's pronghorn and a likely ancestor of the Arabian Oryx. The Osbornoceros lived during the late Miocene between six to seven million years ago and is believed to have have inhabited various lands within North America, with all fossil specimens found within the Chamita Formation in New Mexico. It belonged to the Antilocapridae family, of which every species is extinct except for the present day Pronghorn which strongly resembles the Osbornoceros, both in its physical characteristics and behavior.
Diagram
Diagram of an Osbornoceros. Not all details are correct as scientists cannot fully determine many of its adaptations or its exact height and size.
The Osbornoceros is believed by many scientists to have occupied most areas within North America, but so far to date, all fossil specimens of the Osbornoceros have only been found within the Chamita Foundation in New Mexico, USA. It is widely believed by many that the Osbornoceros existed throughout mainland North America but only within the continent.
At the time, there were no natural barriers such as mountains at the time within North America and the most inhospitable area in North America at the time was the New Mexico/ Texas region and the Greenland region, which was linked to the North American continent by a large land bridge made of ice approximately the same length as the West coast of the United States today. Thus, the food sources and water sources would of been abundant almost everywhere, making it ideal for herds or individuals of Osbornoceros' to travel to. Thus, the only area within the North American continent that the Osbornoceros would have been restricted to was Greenland due to the land bridge which had to be crossed and the sub zero degree temperature that would surely wipe out an antilocaprid such as the Osbornoceros which are believed to have originated from desert areas with a hot and dry climate.
When resting, the Osbornoceros prefers spots under trees or with some sort of shade which can help to block out the sun's rays. It prefers to dig burrows in the ground where it can rest in and thus prevents any predators from spotting it but normally it will rest behind the cover of a bush if possible where it is already highly unlikely from being spotted by predators.
The Osbornoceros is nomadic and travels with others in a herd in search of food and water, traveling to various locations which is connected by land on the North American continent. However, most herds of Osbornoceros were believed to have stayed in New Mexico and Texas as that was where they were most adapted to and also because most only lived an average of a less than five years due to illness and predators.
Being a herbivore, the diet of an Osbornoceros consisted mainly of simple forms of shrubs and grass, but possibly ate other types of vegetation which is unknown due as not a lot of North American plant life can be found from any records. The majority of the Osbornoceros population were believed to have inhabited mainly open grasslands, but were also believed to have existed in large numbers in deserts and brush land, eating vegetation which may be toxic to today's North American livestock which inhabit the same areas.
A map of the late Miocene Era, where the Osbornoceros was believed to have only inhabited the North American mainland as it was separated from all other continents, including South America and Greenland by a cold land bridge
Similar to most of its descendants today such as the Arabian Oryx and Pronghorn, the Osbornoceros chooses to lie still most of the time in one area and only travels in order to get to a food or water source. During its existence, the Osbornoceros always lived in danger as its the population of its predators such as the hare-eating wolf kept on growing in size and thus made it more and more difficult for the Osbornoceros population to live on. Thus, in order to avoid detection the Osbornoceros chooses to lie still most of the time, with the doe only moving once every few hours in order to retrieve food from a source and feed it to the young. This helps the Osbornoceros as it greatly reduces its chance of being killed and eaten by predators which can often outrun an Osbornoceros within a matter of minutes. Environmental pressure that could have given rise to the Osbornoceros' habit of lying still most of the time may be because of the high likelihood of being spotted by predators when on the move, thus making it a lot safer to stay still in a hiding spot and decrease the overall likelihood of being killed by predators.
Strong herd instinct
Another behavioral adaptation of the Osbornoceros is its strong herd instinct. Similar to other antilocaprids and many species of antelope from the past and present, the Osbornoceros always travels with as big a herd as possible, an adaptation for survival and an obvious defensive measure. Herds of Osbornoceros are believed to be an average size of 50, with some reaching close to 100 and proves safer with dozens of eyes glancing away in the distance, giving an early warning in case a predator happens to be nearby. Thus, even when running away as a last resort, the herd would run together in a tight, organized manner in order to avoid a direct confrontation with a predator. Environmental pressure that could have given rise to a strong herd instinct was probably due to high death rates of individual Osbornoceros', and as a large herd is formed, no single predator in their right mind would attempt to attack the Osbornoceros herd unless they are backed by others of their own species.
Structural Adaptations
Series of small horns protruding from skull
Even though not a lot is known about the Osbornoceros due to lack of fossils and specimens, a lot has been determined about its environment, habitat, behavior and physiology through its structural adaptations. The main structural adaptation of the Osbornoceros are its series of small horns which protrude from the skull, used for many defensive purposes and its main tool for survival as well. Ever since the its birth the Osbornoceros is already under danger due to many predators, not only wolves but also birds believed to be the ancestor of the eagle. Thus, the young develop horns quickly in order to help protect itself mainly from big birds whom attempt to prey on them. Once the young get older, both male and female Osbornoceros develop a prominent series of horns used to fend off predators such as the Hare-eating wolf, with birds no longer a threat anymore. Environmental pressure that could have given rise to the series of small horns which the Osbornoceros develops may be due to the fact that as they inhabited a continent with many different forms of predators lurking they needed a weapon to defend themselves, and being herbivores, they could only use their horns as their teeth were not strong enough due to the fact that they only ate simple forms of vegetation.
Long, slender legs
The Osbornoceros inhabited a big continent which was probably filled with many other forms of life and also a lot of surprises, causing it to develop structural adaptations such as long, slender legs which helped it to run very fast and swiftly. The legs of an Osbornoceros most possibly developed due to predators which may also have inhabited the North American continent within the late Miocene era, such as the Hare-eating wolf, which evolved into today's cougar, coyote, and wolf which all inhabit North America. Environmental pressure that could of given rise to the long, slender legs of the Osbornoceros may be due to the fact that as the Osbornoceros had to face all kinds of predators, many which we do not even know of, it had to develop legs which would help it run faster whenever it though it would be in danger. These long, slender legs help the Osbornoceros to run faster than today's leopard and capable of outrunning the cheetah in a long distance race.
Physiological Adaptations
Eyeballs
The Osbornoceros had many physiological adaptations, the most notable one being its eyeballs. The eyeball of an Osbornoceros was approximately four cm in diameter, thus giving it extraordinary eyesight. Since the rods and cones are spread along a horizontal plane, it not only gave the Osbornoceros excellent eyesight but also helped it detect movement up to five kilometers away. Environmental pressure that could have given rise to the extraordinary eyesight of the Osbornoceros may be because that as they spent most of the day staying still and resting in order to stay safe from predators, they would have also spent hours glancing around and focusing into the distance in order to spot predators, thus developing their extraordinary eyesight.
Extinction Pressure
Since little information is known of the Osbornoceros, the reason for its extinction is yet unknown as no solid evidence can be found from the six to seven million year old fossils . However, it is widely believed that as all fossil specimens of the Osbornoceros were discovered within New Mexico, where many similar fossils of the Hare-eating wolf, also known as Canis lepophagus, were discovered, it may have become extinct due to the overwhelming number of predators which also inhabited the regions where herds of Osbornoceros existed, which are mostly in New Mexico and Texas. Furthermore, fossil specimens of the Hare-eating wolf were discovered all around North America, including Tonuco Mountain, Nebraska, Idaho, Utah and Oklahoma, which along with the scarcity of food sources could have led to the extinction of the Osbornoceros. Interestingly, the Hare-eating wolf happened to have evolved into the cougar, gray wolf and coyote of today, which happen to be the predators of the Pronghorn, an artiodactyl mammal which is strikingly similar to an antelope and evolved from the Osbornoceros. Another theory for the extinction of the Osbornoceros was simply because the Osbornoceros could have evolved and diversified into many different species such as the Arabian Oryx or Pronghorn which exist today, and as land bridges formed over and over between North America and Asia, certain species could of traveled across into Asia, Arabia and further into Africa and evolved into different species such as the Beisa Oryx, now native to East Africa.
Osbornoceros
Introduction
The Osbornoceros (Osbornoceros osborni) was a prehistoric antilocaprid which is extremely similar to today's pronghorn and a likely ancestor of the Arabian Oryx. The Osbornoceros lived during the late Miocene between six to seven million years ago and is believed to have have inhabited various lands within North America, with all fossil specimens found within the Chamita Formation in New Mexico. It belonged to the Antilocapridae family, of which every species is extinct except for the present day Pronghorn which strongly resembles the Osbornoceros, both in its physical characteristics and behavior.Diagram
Scientific Classification Table
Habitat and Range
The Osbornoceros is believed by many scientists to have occupied most areas within North America, but so far to date, all fossil specimens of the Osbornoceros have only been found within the Chamita Foundation in New Mexico, USA. It is widely believed by many that the Osbornoceros existed throughout mainland North America but only within the continent.At the time, there were no natural barriers such as mountains at the time within North America and the most inhospitable area in North America at the time was the New Mexico/ Texas region and the Greenland region, which was linked to the North American continent by a large land bridge made of ice approximately the same length as the West coast of the United States today. Thus, the food sources and water sources would of been abundant almost everywhere, making it ideal for herds or individuals of Osbornoceros' to travel to. Thus, the only area within the North American continent that the Osbornoceros would have been restricted to was Greenland due to the land bridge which had to be crossed and the sub zero degree temperature that would surely wipe out an antilocaprid such as the Osbornoceros which are believed to have originated from desert areas with a hot and dry climate.
When resting, the Osbornoceros prefers spots under trees or with some sort of shade which can help to block out the sun's rays. It prefers to dig burrows in the ground where it can rest in and thus prevents any predators from spotting it but normally it will rest behind the cover of a bush if possible where it is already highly unlikely from being spotted by predators.
The Osbornoceros is nomadic and travels with others in a herd in search of food and water, traveling to various locations which is connected by land on the North American continent. However, most herds of Osbornoceros were believed to have stayed in New Mexico and Texas as that was where they were most adapted to and also because most only lived an average of a less than five years due to illness and predators.
Being a herbivore, the diet of an Osbornoceros consisted mainly of simple forms of shrubs and grass, but possibly ate other types of vegetation which is unknown due as not a lot of North American plant life can be found from any records. The majority of the Osbornoceros population were believed to have inhabited mainly open grasslands, but were also believed to have existed in large numbers in deserts and brush land, eating vegetation which may be toxic to today's North American livestock which inhabit the same areas.
Behavioral Adaptations
Lying still in one area most of the time
Similar to most of its descendants today such as the Arabian Oryx and Pronghorn, the Osbornoceros chooses to lie still most of the time in one area and only travels in order to get to a food or water source. During its existence, the Osbornoceros always lived in danger as its the population of its predators such as the hare-eating wolf kept on growing in size and thus made it more and more difficult for the Osbornoceros population to live on. Thus, in order to avoid detection the Osbornoceros chooses to lie still most of the time, with the doe only moving once every few hours in order to retrieve food from a source and feed it to the young. This helps the Osbornoceros as it greatly reduces its chance of being killed and eaten by predators which can often outrun an Osbornoceros within a matter of minutes. Environmental pressure that could have given rise to the Osbornoceros' habit of lying still most of the time may be because of the high likelihood of being spotted by predators when on the move, thus making it a lot safer to stay still in a hiding spot and decrease the overall likelihood of being killed by predators.Strong herd instinct
Another behavioral adaptation of the Osbornoceros is its strong herd instinct. Similar to other antilocaprids and many species of antelope from the past and present, the Osbornoceros always travels with as big a herd as possible, an adaptation for survival and an obvious defensive measure. Herds of Osbornoceros are believed to be an average size of 50, with some reaching close to 100 and proves safer with dozens of eyes glancing away in the distance, giving an early warning in case a predator happens to be nearby. Thus, even when running away as a last resort, the herd would run together in a tight, organized manner in order to avoid a direct confrontation with a predator. Environmental pressure that could have given rise to a strong herd instinct was probably due to high death rates of individual Osbornoceros', and as a large herd is formed, no single predator in their right mind would attempt to attack the Osbornoceros herd unless they are backed by others of their own species.Structural Adaptations
Series of small horns protruding from skull
Even though not a lot is known about the Osbornoceros due to lack of fossils and specimens, a lot has been determined about its environment, habitat, behavior and physiology through its structural adaptations. The main structural adaptation of the Osbornoceros are its series of small horns which protrude from the skull, used for many defensive purposes and its main tool for survival as well. Ever since the its birth the Osbornoceros is already under danger due to many predators, not only wolves but also birds believed to be the ancestor of the eagle. Thus, the young develop horns quickly in order to help protect itself mainly from big birds whom attempt to prey on them. Once the young get older, both male and female Osbornoceros develop a prominent series of horns used to fend off predators such as the Hare-eating wolf, with birds no longer a threat anymore. Environmental pressure that could have given rise to the series of small horns which the Osbornoceros develops may be due to the fact that as they inhabited a continent with many different forms of predators lurking they needed a weapon to defend themselves, and being herbivores, they could only use their horns as their teeth were not strong enough due to the fact that they only ate simple forms of vegetation.Long, slender legs
The Osbornoceros inhabited a big continent which was probably filled with many other forms of life and also a lot of surprises, causing it to develop structural adaptations such as long, slender legs which helped it to run very fast and swiftly. The legs of an Osbornoceros most possibly developed due to predators which may also have inhabited the North American continent within the late Miocene era, such as the Hare-eating wolf, which evolved into today's cougar, coyote, and wolf which all inhabit North America. Environmental pressure that could of given rise to the long, slender legs of the Osbornoceros may be due to the fact that as the Osbornoceros had to face all kinds of predators, many which we do not even know of, it had to develop legs which would help it run faster whenever it though it would be in danger. These long, slender legs help the Osbornoceros to run faster than today's leopard and capable of outrunning the cheetah in a long distance race.Physiological Adaptations
Eyeballs
The Osbornoceros had many physiological adaptations, the most notable one being its eyeballs. The eyeball of an Osbornoceros was approximately four cm in diameter, thus giving it extraordinary eyesight. Since the rods and cones are spread along a horizontal plane, it not only gave the Osbornoceros excellent eyesight but also helped it detect movement up to five kilometers away. Environmental pressure that could have given rise to the extraordinary eyesight of the Osbornoceros may be because that as they spent most of the day staying still and resting in order to stay safe from predators, they would have also spent hours glancing around and focusing into the distance in order to spot predators, thus developing their extraordinary eyesight.Extinction Pressure
Since little information is known of the Osbornoceros, the reason for its extinction is yet unknown as no solid evidence can be found from the six to seven million year old fossils . However, it is widely believed that as all fossil specimens of the Osbornoceros were discovered within New Mexico, where many similar fossils of the Hare-eating wolf, also known as Canis lepophagus, were discovered, it may have become extinct due to the overwhelming number of predators which also inhabited the regions where herds of Osbornoceros existed, which are mostly in New Mexico and Texas. Furthermore, fossil specimens of the Hare-eating wolf were discovered all around North America, including Tonuco Mountain, Nebraska, Idaho, Utah and Oklahoma, which along with the scarcity of food sources could have led to the extinction of the Osbornoceros. Interestingly, the Hare-eating wolf happened to have evolved into the cougar, gray wolf and coyote of today, which happen to be the predators of the Pronghorn, an artiodactyl mammal which is strikingly similar to an antelope and evolved from the Osbornoceros. Another theory for the extinction of the Osbornoceros was simply because the Osbornoceros could have evolved and diversified into many different species such as the Arabian Oryx or Pronghorn which exist today, and as land bridges formed over and over between North America and Asia, certain species could of traveled across into Asia, Arabia and further into Africa and evolved into different species such as the Beisa Oryx, now native to East Africa.Bibliography